A newspaper owned by Rupert Murdoch, criminal shenanigans, a controversial relationship with Scotland Yard detectives and a furious response from the House of Commons. It all takes place in 1970 but details of an extraordinary sequence of events involving the great train robber Ronnie Biggs, the Murdoch empire and the Met police have only just been released by the National Archives.

It was the spring of 1970 and a young Murdoch was just settling in as the owner of the Sun and the News of the World. From Australia came news that another of his papers, the Melbourne Daily Mirror, had been contacted by a lawyer, supposedly acting for Biggs, who had been convicted of the 1963 great train robbery and jailed for 30 years before escaping over the wall of Wandsworth prison in 1965 and vanishing.

Biggs wanted to sell his story, using the money to set up a "trust fund" for his three children. To prove that the story was genuine, Biggs had obligingly appended a fingerprint and signature to each page of the manuscript. But how to check that the dabs were genuine?

This is when, according to Metropolitan police files just released, Scotland Yard became involved. The police were contacted by the the Sun's news editor, Brian McConnell, and invited to a meeting with the paper's editor, Larry Lamb, who had "in his possession a document regarding a crime of importance and wished to hand a copy to the assistant commissioner crime".

At the subsequent meeting at the Sun, Lamb handed the documents to Commander Wally Virgo. "He also pointed out that each page bore a fingerprint and a signature and wondered if 'the Yard' could oblige by authenticating same," according to the police report of the meeting. "He went on to say that he realised that some parts of the documents were libellous but, having taken legal advice, his newspaper would not publish anything detrimental to the police."

But what about catching Biggs, at the time one of the most wanted men in the world? "Mr Virgo made it clear to the editor that it was his bounden duty to pass any information he might receive notifying the whereabouts of Biggs to police and this the editor said he would be happy to do... Mr Lamb emphasised throughout that he had no personal contact with either Biggs or any person who might be considered his agent."

The Yard obligingly checked out the 77 typeset pages. A Commander Peat identified the fingerprint as probably those of Biggs although he thought it could have been taken from a cast or stamp of the original.

Mr Frydd of the Forensic Science Laboratory was very sceptical about the signatures which he deduced were "not in the least bit likely to have been made by Ronald Biggs." He concluded they had "certain possible female characteristics".

Advice was taken from the Met solicitor who reckoned that they could not stop publication and, if they tried, it could "lead to unfavourable comment about the police".

Virgo was deputed to return the documents and confirm their authenticity and publication went ahead.

Then came trouble from Australia. A furious commissioner of police in New South Wales, Norman Allan, rang the Yard late at night on 19 April, having learned of the imminent publication of the memoirs in Australia.

"He expressed amazement that New Scotland Yard had supported this newspaper venture and felt that it was holding both his force and ours up to ridicule," according to the Met record of the call. "He pointed out that, whilst police in both countries could not find Biggs, a solicitor had been able to receive from him his story with his fingerprint and signature. He felt that the police by confirming the authenticity of the fingerprint were in fact enabling Biggs to obtain further money to assist in his escape. He did not for a moment believe that any money from the story would be placed in a trust fund for Biggs's children."

The publication caused outrage in Britain, too. Arthur Lewis, the Labour MP for West Ham North, asked the home secretary, James Callaghan, whether he had "considered the information... showing that a newspaper has paid either Ronald Biggs or his agents money in relation to the mail bag robbery, whether he will take action against the newspaper concerned for aiding and abetting a convicted criminal".

Allan suggested the Murdoch papers were "giving comfort and aid to an escaped prisoner."

The CID seemed stung by any suggestion that they had been slow off the mark in pursuing this latest lead in the hunt for Biggs: "Police efforts to re-arrest Biggs are as intense now as ever they were. No effort is spared to achieve this object." They concluded, however, that no action could be taken against the Sun.

What Lamb and his colleagues were not to know was that Virgo came from the top end of the Yard's "dodgy geezer" scale and was soon to become a big story himself. He had been receiving £2,000 a month – plus Christmas bonus – in bribes from Soho pornographer, Jimmy Humphreys, who kept a meticulous note of all his payments. Virgo was arrested, charged, jailed for 12 years, cleared on appeal because of a misdirection by the judge, and died a few years later.

"I don't think [corrupt police] really thought of it in terms of corruption," said Peter Scott, the jewel thief dubbed "king of the cat burglars". "They just thought it was a perk."

Lamb, who gave the world the Page 3 model, died in 2000 and McConnell, who was shot and wounded when he came between a kidnapper and Princess Anne in 1974, has also gone to the newsroom in the skies.

Biggs had dealings again with the British media when the Daily Express tracked him down to Rio de Janeiro in 1974 but he avoided extradition by fathering a Brazilian son. Eventually, sick and broke, he flew back to England – courtesy of the Sun once more – to give himself up in 2001. He was released from prison in 2009 after suffering a series of strokes. This time there was no need to check his fingerprints.